1. Field of the Invention
This invention is an imaging spectrometer useful for measuring the spectral composition of gases emanating from a gas leak at a remote location, and, more particularly, provides a method and apparatus for locating gas leaks.
2. Prior Art
Gas producers and distributors lose millions of dollars annually due to gas leakage from a distribution line, processing or containment facility. A portable instrument with the capability to remotely detect and image gases, including gas leaks, is needed. Such a device and method for finding and identifying gas leaks should preferably further provide an analysis of the gas including chemical species and concentrations.
Spectrophotometers (color meters) are widely used in the area of target recognition. The principle underlying the use of spectrophotometers in target recognition is that different targets reflect, emit or absorb light differently. Alternatively, different targets represent independent light sources, the light emanating from each target having an observable spectra which is an identifiable inherent characteristic of that target which may be used for target identification.
Image multispectral sensing (IMSS) records the spectrum of individual luminous objects (targets) within an image or scene. IMSS is capable of simultaneously recording the spectrum of light emerging from many different discrete light sources contained within a single field of view. U.S. Pat. No. 5,479,258 to Hinnrichs et al., the contents of which is incorporated herein by reference thereto, discloses an image multispectral sensing device, which provides good spectral resolution for images comprising luminous point objects which have good contrast ratios with respect to the background. The ability of IMSS spectrometers to distinguish between an object and a background may be extended to the detection of a non-homogeneous distribution of gases in a volume of gas. There is a need for an IMSS apparatus which is adapted to be portable and operable for detecting gas leaks at remote locations.
It is an object of this invention to provide a spectrometric apparatus for measuring the spectral composition of infrared, visible or ultraviolet light emanating from a volume of gas located at a distance from the apparatus.
It is yet another object of this invention to provide a imaging spectrometer apparatus which can determine the spectral composition of light emanating from different portions of a large volume of gas comprising a remote field of view.
It is another object of this invention to provide a imaging spectrometer apparatus useful for comparing the spectral composition of light (color signature) emanating from a remote luminous volume of gas within a field of view with the color signature of previously identified luminous gases or mixtures of gases.
It is a particular object of the invention to provide a IMSS apparatus operable for performing the above objects and which can detect the presence of a gas leak from a gas containment device, or components is a processing or distribution system.
These and other aspects of the invention will soon become apparent in view of the drawings and description of the preferred embodiments.